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21.
论证了将软件编码的数字电视传输流数据文件转换成并行码流输出的软硬件实施方案 ,并给出了研制的系统。系统基于微机构筑 ,工作于 Windows环境 ,编码制式、参数以及输出码率等可灵活设定 ,可作为数字电视系统测试信号源。  相似文献   
22.
本文针对目前日益凸显的电子文档泄漏问题,对国内电子文档保护现状和存在的问题进行了分析,从原理和实现方式等方面对比了主流文档保护产品,总结了在建立电子文档防扩散体系时应确定的防护原则,并对管理和技术要点进行了分析,为电子文档防扩散系统的建设提供了建议。  相似文献   
23.
Xia  Lei  Lv  Jiancheng  Xie  Chunzhi  Yin  Jing 《Applied Intelligence》2021,51(11):8334-8348

In the context of human-robot and robot-robot interactions, the better cooperation can be achieved by predicting the other party’s subsequent actions based on the current action of the other party. The time duration for adjustment is not sufficient provided by short term forecasting models to robots. A longer duration can by achieved by mid-term forecasting. But the mid-term forecasting models introduce the previous errors into the follow-up forecasting and amplified gradually, eventually invalidating the forecasting. A new mid-term forecasting with error suppression based on restricted Boltzmann machine(RBM) is proposed in this paper. The proposed model can suppress the error amplification by replacing the previous inputs with their features, which are retrieved by a deep belief network(DBN). Furthermore, a new mechanism is proposed to decide whether the forecasting result is accepted or not. The model is evaluated with several datasets. The reported experiments demonstrate the superior performance of the proposed model compared to the state-of-the-art approaches.

  相似文献   
24.
适用于复杂环境下的实时目标跟踪技术   总被引:1,自引:0,他引:1  
针对复杂环境下目标跟踪过程中目标存在旋转、视角、尺度等变化以及噪声干扰的问题,提出了一种基于尺度不变特征与快速模板匹配相结合的目标跟踪技术;该技术通过分别提取预先存储模板和实时采集图像的尺度不变特征,建立初始模板;采用菱形搜索策略对模板的低分辨率子图和待跟踪图像的低分辨率子图进行快速互相关检测,根据检测结果在该帧高分辨率图像中建立紧凑ROI,在此区域内进行模板匹配,对目标进行精确定位;在目标跟踪的过程中采用自适应模板更新策略,以保证在目标发生变化时跟踪的稳定性;实验结果表明,该技术在稳定性、准确性和实时性等方面均优于传统方法。  相似文献   
25.
《数字电路》是中职电类专业的一门专业基础课程。结合目前中职学校教学现状中存在的问题,如何让学生把这门课学好,笔者从精选教材、课堂导入、教学手段、考核评价等方面进行了探讨。指出了只有充分激发起学生的学习兴趣和学习积极性,才是提高教学质量的关键。  相似文献   
26.
Ma  Xin  Zhang  Guoqiang  Li  Fengting  Jiao  Mingyang  Yao  Shunyu  Chen  Zhipeng  Liu  Ziyong  Zhang  Yongyu  Lv  Ming  Liu  Licheng 《Catalysis Letters》2021,151(10):2939-2949
Catalysis Letters - Microbial electrosynthesis (MES) is an effective approach to driving the CO2 reduction to multi-carbon organic products using renewable energy. In this work, the MES of acetate...  相似文献   
27.
在极软岩的地质条件下,采用自创的新型注浆设备,通过不同入岩深度及成桩措施进行桩基施工,根据静载荷试验进行分析对比,得出入岩深度增加和后注浆对桩基沉降量的影响及自创注浆设备的实用性.  相似文献   
28.
A series of high oil-absorption resins with low cross-linking degree were synthesized by suspension polymerization using stearyl methacrylate(SMA), 2-Ethylhexyl methacrylate(EHMA), and styrene(St) as monomers.Response surface methodology(RSM) with central composite design(CCD) was also applied to determine the optimal parameters that are mainly known to affect their synthesis. Thus, the effects of the monomer mass ratio(EHMA:SMA), the rigid monomer(St) dosage, the porous agent(acetone) dosage, and their pairwise interaction on the resin's oil-absorption capacity were analyzed, highlighting PSES-R_2 as the resin with the optimum performance. The pure oil-absorption rates of PSES-R2 for gasoline, diesel, and kerosene were 11.19 g·g~(-1),16.25 g·g~(-1), and 14.84 g·g~(-1), respectively, while the oil removal rates from oily wastewater were 98.82%,65.11%, and 99.63%, respectively.  相似文献   
29.
Introduction of C4 photosynthetic traits into C3 crops is an important strategy for improving photosynthetic capacity and productivity. Here, we report the research results of a variant line of sorghum–rice (SR) plant with big panicle and high spikelet density by introducing sorghum genome DNA into rice by spike-stalk injection. The whole-genome resequencing showed that a few sorghum genes could be integrated into the rice genome. Gene expression was confirmed for two C4 photosynthetic enzymes containing pyruvate, orthophosphate dikinase and phosphoenolpyruvate carboxykinase. Exogenous sorghum DNA integration induced a series of key traits associated with the C4 pathway called “proto-Kranz” anatomy, including leaf thickness, bundle sheath number and size, and chloroplast size in bundle sheath cells. Significantly, transgenic plants exhibited enhanced photosynthetic capacity resulting from both photosynthetic CO2-concentrating effect and improved energy balance, which led to an increase in carbohydrate levels and productivity. Furthermore, such rice plant exhibited delayed leaf senescence. In summary, this study provides a proof for the feasibility of inducing the transition from C3 leaf anatomy to proto-Kranz by spike-stalk injection to achieve efficient photosynthesis and increase productivity.  相似文献   
30.
In this study, a kind of imidazole type poly(ionic liquid) ([PEP-MIM]Cl) is synthesized, which can disperse carbon effectively. [PEP-MIM]Cl is used as an intermediate to coat carbon on the poly(acrylic acid)(PAA-co-MBA) via ion exchange to obtain conductive polymer composite (CPC). A series of characterizations are performed. Experiments show that carbon can be coated on the PAA-co-MBA uniformly, and compared with using carbon as filler, this method requires less carbon to achieve good conductive performance. The carbon layer on the polymer's surface is enriched via the swelling-shrinking properties of PAA-co-MBA according to the SEM images. Furthermore, in combination with 3D printing technology, PAA-co-MBA can be designed into different shapes to achieve various functions such as pressure-sensing element. Finally, a new type of CPC named carbon clad polymeric laminate (CCPL) is prepared by using the carbon coating method and 3D printing technology. It has the potential to replace copper clad laminate (CCL) and printed circuit board (PCB), to a certain extent. This technology expands the preparation method and application of the CPC such as flexible and wearable conductive fabrics.  相似文献   
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